Polyarylene sulfide (hereinafter, also referred to as “PAS”), represented by polyphenylene sulfide (hereinafter, also referred to as “PPS”), is an engineering plastic having excellent heat resistance, chemical resistance, flame retardancy, mechanical strength, electrical characteristics, dimensional stability, and the like. PAS has been widely used in a wide variety of fields, such as electric/electronic devices and devices for automobiles, because PAS can be formed into various shaped products, films, sheets, fibers, and the like by ordinary melt processing methods, such as extrusion molding, injection molding, and compression molding.
As a representative method of producing PAS, a method in which a sulfur source and a dihalo aromatic compound are reacted in an organic amide solvent such as N-methyl-2-pyrrolidone (hereinafter, also abbreviated as “NMP”) has been known (e.g. methods described in Patent Documents 1 and 2).